Study On The Characteristics Of Air Pollution And Causes Of Heavy Pollution In Suihua

Suihua,as a special agricultural city in Heilongjiang Province,plays a vital role in the joint prevention and control of heavily polluted weather in the region of Harbin-Daqing-Suihua.However,the current research on the characteristics of air pollution and the causes of heavy pollution in this city is still in a blank stage.To explore and elaborate on the above issues is currently an urgent task.This research is of great significance to the air pollution control in Suihua and even the joint prevention and control of heavily polluted weather in the whole region of Harbin-Daqing-Suihua.This study uses the spatiotemporal characteristics of air pollution in Heilongjiang Province from 2017 to 2019 as the background,and analyzes the main pollutants(PM_2.5,PM₁₀,SO₂,NO₂,CO,and O₃)through Arc GIS,which shows that Suihua' s degree of air pollution in the whole province.Analysis shows that the air pollution in Heilongjiang Province is mainly particulate pollution,especially Harbin and Suihua.The analysis of the characteristics of air pollution in Suihua by Origin and R language shows that the seasonal concentrations of PM_2.5,PM₁₀,SO₂ and CO are higher in spring and winter than autumn and summer,NO₂ is higher in autumn and winter than spring and summer,and O₃ is higher in spring and summer than autumn and winter.Except for O₃ which changes to an inverted "U" shape of days and months,the remaining major pollutants all show a "U" shape change.The concentration of O₃ changes with hours,its curve has a single-peak characteristic,and the rest have a double-peak characteristic.PM_2.5,PM₁₀ and O₃ are the primary pollutants in Suihua,and correlation analysis shows that AQI is highly correlated with PM_2.5 and PM₁₀ at significant levels.At the same time,the correlation between meteorological elements and main pollutant concentrations was studied through the Pearson correlation coefficient in SPSS software.The results show that,except for PM₁₀ and the wind speed,which are weakly positively correlated,the rest of the pollutants are negatively correlated.O₃ is significantly positively correlated with temperature,while other pollutants are negatively correlated.The heavy pollution period in Suihua was selected as the research object,that is,straw open burning period,spring sand and dust period and winter haze period.The analysis results of the pollution process in the three periods showed that the straw open burning period and winter haze period were based on PM_2.5,while PM₁₀ is the primary pollutant in the spring dust period,and the meteorological conditions that are not conducive to the diffusion of pollutants were explored.At the same time,combined with HYSPLIT / Meteo Info simulation,the results showed that the potential source area during the open burning period was the fan-shaped distribution of Suihua as the center to the southwest and northwest,the potential source area in the spring and dust period is Suihua as the center,showing the spindle-shaped distribution from northeast to southwest,and the potential source area in the winter haze period is radially distributed around the center in Suihua.Open burning of straw occupies a dominant position in the influencing factors of heavily polluted weather in Suihua,while the contribution of other periods is low.Therefore,the open burning of straw in Suihua should be controlled.For the project,the standard pollution load method is adopted to determine the basic pollutant control items as PM_2.5 and NOX,and the pollution control items are selected as CO,SO₂ and CO₂ and NMVOCs with large emissions in the emission list,and then the straw burning authorization is given.The burning conditions are: the burning place must not belong to the smoke sensitive area,the burning time is 10 am and 5 pm,the straw moisture content is less than 10%,and the burning straw is stacked in vertical stacks or loose stacks.The weather conditions are: The smoke diffusion index DI is in the range of 3000 ? 5000m²/s,the relative humidity is less than 50%,the vertical decrease rate of air temperature is higher than 0.98 ?/100 m,and the air quality index AQI is less than 100.At the same time,supplemented by education and publicity methods,strengthening supervision and law enforcement control,combined with incineration evaluation and feedback,constantly revise and improve the control plan.Firstly,the pollutant control items are selected based on the emission list,and the equivalent pollution load method is used to determine the basic control pollutant items as PM_2.5 and NOX,and the selective control pollutant items are selected as CO and SO₂,at the same time,CO₂ and NMVOCs with large emissions in the emission list are also determined.After the authorization of straw burning,the given burning conditions are: the burning location must not belong to the smoke sensitive area,the burning period is from 10 am to 5 pm,the straw moisture content is less than 10%,and the straw is stacked in a vertical or loose manner.The meteorological conditions are: the smoke diffusion index DI is in the range of 3000 ? 5000m²/s,the relative humidity is less than 50%,the vertical decrease rate of air temperature is higher than 0.98 ?/100 m,and the AQI is less than 100.At the same time,the government should strengthen education and publicity,strengthen supervision and law enforcement,at the same time,continuously revise and improve the management and control plan based on the evaluation and feedback of incineration.The proposal of this plan can not only guide the reasonable burning of straw and curb air pollution,but also take into account the actual needs of agricultural activities,and provide a certain reference value for the implementation of straw burning in Heilongjiang Province.